Epidemiological survey of elderly patients diagnosed with COVID-19 at mobile field hospitals

Abstract

BACKGROUND:

During the COVID-19 pandemic, the mobile field hospital, a rapidly deployable healthcare facility for emergency care, was effective in ensuring rapid diagnosis and treatment of patients with mild or asymptomatic SARS-CoV2 infections, effectively preventing the spread of COVID-19.

OBJECTIVE:

We conducted a survey to gain a thorough understanding of the epidemiological traits among the elderly who contracted the Omicron variant of the SARS-CoV-2 virus at a mobile field hospital set up at the National Exhibition and Convention Center (Shanghai).

METHODS:

A cross-sectional study approach was employed to examine various factors such as demographic characteristics, clinical features, vaccination status, and nucleic acid testing. We utilized the DezhenTech Integrated Electronic Medical Record Platform (Municipal Isolation Hospital) to collect data and focused on elderly individuals infected with COVID-19 in the fifth isolation zone of the mobile field hospital set up at the National Exhibition and Convention Center (Shanghai). The patients were categorized into different age groups for analysis.

RESULTS:

Among the 3,183 elderly patients, 54.7% were males and 45.3% were females, with an average age of 65.32 $\pm$ 4.41 years. Among them, 47.8% (1523/3183) were 60–64 years old, 34.0% (1082/3183) were 65–69 years old, 14.0% (444/3183) were 70–74 years old, 3.2% (103/3183) were 75–79 years old, and 1.0% (31/3183) were $⩾$ 80 years old. The majority (95.7%) of the elderly patients with chronic conditions had hypertension, diabetes, and coronary heart disease. The first viral nucleic acid screening showed a higher positive rate in the community and hospital fever clinics. The cumulative positive rate of the nucleic acid test in the mobile field hospital was 38.7%. The average CT value of the COVID-19 ORF1ab gene was 34.56 $\pm$ 5.98, while the average CT value of the N gene was 33.10 $\pm$ 6.50. The patients took an average of 3.40 $\pm$ 0.45 days to test negative, with a positive rate of 15.4% and an average hospital stay of 7.45 $\pm$ 0.53 days. The overall rate of COVID-19 vaccine coverage was 68.0%, with an enhanced coverage rate of 40% and a non-coverage rate of 29.3%.

CONCLUSIONS:

The overall prognosis for elderly patients who experienced a mild or asymptomatic SARS-CoV-2 Omicron infection at the mobile field hospital was favorable, although the vaccination rate in general was not high. By effectively managing underlying health conditions, the duration of their hospital stay in the mobile field hospital was reduced.